The present invention relates to plastic modules, conveyor belts formed from plastic modules, and methods for assembling and disassembling pivotably connected plastic modules.
Conveyor belts formed from plastic modules are used in a wide variety of industrial and commercial settings to transport a myriad of items, e.g., everything from apples to zippers. Each module has a body which may be solid or may comprise a lattice of structural elements or struts, and the upper surfaces of the modules serve as the conveying surface for the items being transported. The ends of the body have one or more holes or apertures in them, and adjacent plastic modules are pivotably connected to one another end-to-end, and/or side-to-side, by pivot rods inserted in the apertures. For example, the apertures at one end of the body of one plastic module are aligned with the apertures at the other end of the body of the adjacent plastic module and a pivot rod may be inserted through the aligned apertures, pivotably connecting the plastic modules. Any number of plastic modules may be connected end-to-end, as well as side-by-side, by pivot rods to form a conveyor belt of any convenient length and width. For example, thousands or more plastic modules may be pivotably connected by thousands of pivot rods to form a conveyor belt hundreds of feet long.
While plastic conveyor belts have proven highly reliable, the assembly of conventional plastic conveyor belts has been a difficult, time-consuming process. For example, many conventional modules include a stop member. Before a pivot rod can be inserted in one direction into the apertures of the modules, a stop member must be moved in another direction out of the path of insertion of the pivot rod. Once the pivot rod is fully inserted, the stop member may be returned to its original position, locking the pivot rod in place within the apertures. This process of moving a stop member in one direction, inserting a pivot rod in another direction, and returning the stop member to its original position greatly complicates the process of forming a conveyor belt, especially a conveyor belt having thousands of modules and pivot rods.
The present invention has many advantages and overcomes several problems associated with conventional plastic module conveyor belts, including the problems set forth above.
In accordance with one aspect of the invention, a module for a plastic conveyor belt comprises a body and a resilient stop cooperatively arranged with the body. The body has at least one aperture for receiving a pivot rod. The resilient stop is bendable in the direction of insertion of a pivot rod in the aperture to an extended position allowing a pivot rod to be positioned in the aperture. The resilient stop further has a non-extended position which resists removal of a pivot rod from the aperture.
In accordance with another aspect of the invention, a conveyor belt comprises first and second plastic modules, a pivot rod, and a resilient stop. The pivot rod pivotably connects the first and second plastic modules along a pivot axis. The resilient stop has a non-extended position which resists removal of the pivot rod. Further, the resilient stop is bendable in the direction of the pivot axis toward the pivot rod to an extended position which allows removal of the pivot rod from the first and second plastic modules.
In accordance with another aspect of the invention, a method of assembling first and second plastic conveyor modules comprises inserting a pivot rod into apertures in plastic conveyor modules, including bending a resilient stop in the direction of insertion of the pivot rod. The method further comprises positioning the pivot rod in the apertures, including moving the pivot rod beyond the resilient stop wherein the resilient stop returns to a position resisting removal of the pivot rod.
In accordance with another aspect of the invention, a method of disassembling first and second pivotably connected plastic conveyor modules comprises bending a resilient stop in the direction of the pivot rod axis and removing the pivot rod from apertures in the first and second conveyor modules.
In accordance with another aspect of the invention, a method of maintaining a pivot rod in an aperture of a plastic conveyor module comprises reacting a resilient stop against outward axial movement of the pivot rod , the resilient stop extending at an obtuse angle toward the pivot rod.
In accordance with another aspect of the invention, a module for a plastic conveyor belt comprises a body and a resilient stop. The body has at least one aperture defining an axis. The resilient stop is cooperatively arranged with the body. The resilient stop has a non-extended position and is bendable in the direction of the axis toward the aperture to an extended position. The resilient stop is radially spaced from the axis a greater distance in the extended position than in the non-extended position.
In accordance with another aspect of the invention, a module for a plastic conveyor belt comprises a body and a resilient stop cooperatively arranged with the body. The body has at least one aperture. The resilient stop has a non-extendable position which occludes at least a portion of the aperture. The resilient stop is bendable in a direction toward the aperture to an extended position which does not occlude any portion of the aperture.
Modules, conveyor belts, and methods embodying the invention represent a significant advance in the art. Not only is the pivot rod reliably held in position by a stop member pivotably connecting the modules, but the assembly of the modules to form the conveyor belt is remarkably easy. As the pivot rod is inserted into the apertures of the modules, the pivot rod can contact the stop member and bend the stop member in the direction of insertion to an extended position out of the way of the pivot rod. Once the pivot rod is fully inserted and positioned within the apertures, the pivot rod no longer contacts the stop member, which, in turn, moves to a non-extended position blocking removal of the pivot rod. This greatly facilitates automation of the assembly of the plastic modules to form a conveyor belt because no separate step is needed to move a stop member out of the way of the pivot rod. The pivot rod automatically moves the stop member to an extended position simply by inserting the pivot rod straight into the apertures. Further, the pivot rod can be inserted into the apertures without bending the pivot rod or negotiating any non-linear paths through the apertures.